[Elecraft] K2 Sidetone

[Phil Wheeler]

What Don says is right on!  I have K2/100 #380 and 
have done all the mods -- and they were all worth 
doing :-)

73, Phil W7OX

On 7/3/16 2:19 PM, Don Wilhelm wrote:
> Frank,
>
> That mod is not for all K2s - the K2 design was 
> changed to produce a more sine-wave sidetone.  
> Look closely at the information below.
>
> If your K2 serial number is lower than 3000 - 
> *and* you have not installed the K2ATOB mod kit, 
> then that can be a worthwhile change.
> Be aware that this published mod is quite old, 
> and will cause problems if you attempt to apply 
> it to a K2 above SN3000 or one which has been 
> upgraded with the A to B mods.
>
> The sidetone changes made with the A to B kit 
> and K2s above SN 3000 are not exactly the same 
> as this mod, but do essentially the same thing, 
> but with slightly different component values.
>
> If your K2 is below SN3000 and has not yet had 
> the A to B kit installed as well as the other 
> mod kits indicated on the A to B Instruction 
> sheets, then I recommend you do those upgrades 
> instead of just adding the sidetone mod.  The 
> temperature stability and electrical stability 
> of your older K2 will be improved substantially.
>
> If the serial number is below 2560, you will 
> also benefit by changing the IF crystals on both 
> the base K2 and the KSB2 option for a smoother 
> filter response.  Look at the markings on the 
> crystals - the new crystals have a "-S" suffix 
> marked on them.  If it is anything else, you 
> have the older crystals.  The new crystals were 
> shipped with kits beginning at SN 2560.
>
> 73,
> Don W3FPR
>
> On 7/3/2016 4:43 PM, kg9hfrank at gmail.com wrote:
>> So I have had some quality time with my K2 this 
>> weekend.
>> I am thinking of doing this modification to my 
>> sidetone, has anyone tried it?
>>
>> http://qrpzone.com/elecraft-k2-side-tone-mod/
>>
>> Seems pretty easy to do and I have always 
>> thought it was “my ears”.
>>
>> Comments?